Lenormandia pardalis J.Agardh

Scientific Description

Habit and structure. Thallus medium to dark brown-red, 5–10 cm high, membranous, erect, irregularly branched from the frond surface, primary and secondary blades 3–7 cm long and 4–9 mm broad, ovate to oblong but basally constricted and with rounded apices, margins entire and sometimes slightly involute; midrib faint to distinct; tertiary blades smaller, ovate. Holdfast discoid to fibrous, 2–3 mm across; epilithic or epiphytic. Structure. Apices cleft, apical cells conical, 40–60 µm in diameter (including thick walls), axial cells cutting off 5 pericentral cells, 2 lateral ones on each side and a ventral cell, with the lateral cells becoming interposed to form the mainly one-cell broad medulla, with a cortex 1(–2) cells thick. Surface appearance clearly rhombic areolate, cortical cells irregularly arranged, 15–40 µm across, L/D 1–2. Trichoblasts adventitious, scattered on the surface, arising from cortical cells, much branched, 0.7–1.2 mm long, basal cells 16–25 µm in diameter, L/D 1–2. Cortical cells uninucleate, medullary cells multinucleate; rhodoplasts discoid, chained in larger cells.

Reproduction. Gametophytes dioecious. Procarps occur in clusters on trichoblasts on the blade surface, soon on polysiphonous branches. Carposporophytes with a basal fusion cell, much branched gonimoblast and clavate carposporangia 50–90 µm in diameter. Cystocarps stalked, globose, 500–800 µm in diameter; pericarp ostiolate, 4–7 cells thick. Spermatangial organs in dense clusters on branches of surface trichoblasts, ovoid, 45–75 µm in diameter, L/D 1.5–2. Tetrasporangial stichidia in clusters on blade surfaces, 300–600 µm long and 200–300 µm broad, ovoid, slightly compressed, corticated, with 2 tetrasporangia per segment, 70–120 µm in diameter.

Distribution.Yanchep, W. Aust., to Gabo I., Vic. and Deal I., Bass Strait.

[After Womersley, Mar. Benthic Fl. Southern Australia IIID: 387 (2003)]